F[C:2]1[CH:7]=[C:6]([F:8])[CH:5]=[C:4]([O:9][CH3:10])[C:3]=1[N+:11]([O-:13])=[O:12].[OH-:14].[Na+].Cl>CS(C)=O.O>[F:8][C:6]1[CH:5]=[C:4]([O:9][CH3:10])[C:3]([N+:11]([O-:13])=[O:12])=[C:2]([OH:14])[CH:7]=1To a solution of 1,5-difluoro-3-methoxy-2-nitro-benzene (20 g, 105 mmol) in dimethylsulfoxide (50 ml) is added a 10N aqueous solution of sodium hydroxide (31.5 ml) and the mixture is stirred at room temperature for 18 h and at 60° C. for 3 h. After completion of reaction (monitored by TLC), the mixture is diluted with water (50 ml), acidified with 2N hydrochloric acid to pH 3 and extracted with ethyl acetate (3×100 ml). The combined organic layers are washed with water (50 ml), brine (50 ml), dried over sodium sulfate and concentrated in vacuo. The crude product is purified by flash column chromatography (15% ethyl acetate/hexane) to yield 5-fluoro-3-methoxy-2-nitro-phenol (12.0 g, 63.5 mmol, 60%).
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